|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Environmentally Assisted Cracking: Theory and Practice
||Hydrogen Embrittlement Mediated by Reaction between Dislocation and Grain Boundary in Iron
||Liang Wan, Wen-Tong Geng, Jun-Ping Du, Akio Ishii, Hajime Kimizuka, Shigenobu Ogata
|On-Site Speaker (Planned)
The tensile response of grain boundaries in α-Fe was studied by atomistic modeling method with a density functional theory based empirical interatomic potential together with a bicrystal model. With certain amount of H atoms introduced, fracture of the bicrystal will be accomplished by void nucleation and growth at grain boundary. Importantly, it is recognized that the void nucleation is preceded by a certain amount of dislocations emission and impingement at the grain boundary. Analysis shows that dislocations emission and impingement on the grain boundary makes the grain boundary transform to an activated state of more irregular structure locally, and introduces a local stress concentration. The activation of the grain boundary will facilitates decohesion of the grain boundary with the help of H atoms. The local activation of grain boundaries by reaction with dislocations is deemed to be a key step in the hydrogen embrittlement mechanism in metals.
||Planned: Supplemental Proceedings volume